Information providing device and method

ABSTRACT

The authentication function ( 221 ) authenticates a PDA. The content database ( 224 ) holds the usage conditions of a content and the information about the content. The communication function ( 225 ) controls the reception of the usage conditions and the content information, both transmitted from the PDA. The content management function ( 222 ) updates the usage conditions and the content information received, on the basis of the usage conditions and the content information held. The desired content is thereby retrieved quickly.

TECHNICAL FIELD

[0001] The present invention relates to an information providingapparatus, an information providing method, an information processingdevice, an information processing method, and a recording medium. Moreparticularly, the invention relates an information providing apparatus,an information providing method, an information processing device, aninformation processing method, and a recording medium, for manipulatingcontent the operation on which is restricted by the usage conditions.

BACKGROUND ART

[0002] As digital devices including computers have become more advanced,digital content (hereafter simply referred to as content)of such asmusic and images has come to be handled.

[0003] Generally, content is stored in a directory structure on astorage unit arranged internal or external to a digital device. Contentcan be attached with additional information such as its name, recordingdate, and information indicative whether the content is read only ornot.

[0004] Executing a predetermined program, the personal computer caneasily execute content retrieval, movement, and copy for example. Forexample, Internet Explorer (trademark) (produced by MicrosoftCorporation) displays content in a tree structure. If plural digitaldevices are connected to the personal computer which executes InternetExplorer, it can display all content stored in all the connecteddevices.

[0005] Internet Explorer displays types of content with icons. Also,when an icon representing a particular piece of content has been draggedand dropped, Internet Explorer copies or moves that content accordingly.

[0006] Thus, the content movement and copy operations can be executedeasily, thereby causing problems associated with content copyrightprotection.

[0007] To solve the problems, copyright protection technologies are usedby which content is encrypted and content usage conditions and a contentkey for content encryption (or decryption) are attached to the encryptedcontent.

[0008] The content usage conditions include reproduction count,reproduction period, movement count, copy count, and checkout count forexample. The copyright protection technologies become available onlywhen the encrypted content attached with its usage conditions andcontent key and a device compatible with a particular copyrightprotection technology are ready for use.

[0009] One of the problems involved in the related art is thatcopyright-protected content cannot be moved or copied unless a procedurebased on a particular copyright protection technology is followed. Therelated-art technologies are unable to move or copy anycopyright-protected content without requiring users to executecumbersome operations.

[0010] Another problem is that, as the number of content handlingdevices and the volume of content increases, it becomes more difficultfor users to retrieve desired pieces of content.

DISCLOSURE OF THE INVENTION

[0011] The present invention has been made in view of the foregoing. Anobject of the invention is to enable users to promptly retrieve desiredcontent, to move easily or copy copyright-protected content inaccordance with their usage conditions.

[0012] An information providing apparatus according to the presentinvention comprises: apparatus authentication means for authenticating afirst information processing device though a transmission path; holdingmeans for holding the usage conditions of content and the informationabout the content; first reception control means for controlling thereception of the usage conditions transmitted from the first informationprocessing device and the reception of the information about thecontent; and updating means for updating the usage conditions and theinformation, held in the holding means, on the basis of the usageconditions and the information which have been received.

[0013] The information providing apparatus may further comprisestransmission control means for controlling the transmission of theinformation to a second information processing device if the informationhas been updated.

[0014] The information providing apparatus may further comprise displaycontrol means for controlling the displaying of the informationassociated with the content.

[0015] The information providing apparatus may further comprise a secondreception control means for controlling the reception of a contentoperation request transmitted from the first information processingdevice; and transmission control means for controlling the transmissionof the content operation request to the second information processingdevice.

[0016] The information providing apparatus may further comprise meansfor determining whether to permit an operation of the content, inaccordance with the usage conditions held; and operating means foroperating the content if it has been determined that the operation ofthe content is permitted.

[0017] The information providing apparatus may further comprise userauthentication means for authenticating a user of the informationproviding apparatus.

[0018] In the information providing apparatus, the holding means furtherholds a flag indicating whether or not the first information processingdevice is connected to the information providing apparatus. The updatingmeans can update the flag.

[0019] An information providing method according to the inventioncomprises the steps of: authenticating an information processing devicethrough a transmission path; holding the usage conditions of content andthe information about the content; controlling the reception of theusage conditions and the reception of the information about the content;and updating the usage conditions and the information, which have beenheld, on the basis of the usage conditions and the information whichhave been received.

[0020] A recording medium according to the invention records a programdescribing the steps of: authenticating an information processing devicethough a transmission path; holding the usage conditions of content andthe information about the content; controlling the reception of theusage conditions and the reception of the information about the content;and updating the usage conditions and the information, which have beenheld, on the basis of the usage conditions and the information whichhave been received.

[0021] An information processing device according this inventioncomprises: holding means for holding the usage conditions of content andthe information associated with the content; first updating means forupdating the usage conditions and the information, held in the holdingmeans, in accordance with the operation of the content if the contenthave been operated; apparatus authentication means for authenticating aninformation providing apparatus though a transmission path; firsttransmission control means for controlling the transmission of the usageconditions and the information to the information providing apparatuswhen the content are operated; reception control means for controllingthe reception of the usage conditions and the information associatedwith the content, which have been transmitted from the informationproviding apparatus; second updating means for updating the usageconditions and the information, both held, on the basis of the usageconditions and the information which have been received; and displaycontrol means for controlling the displaying of the information.

[0022] The information processing device may further comprise means fordetermining whether to permit an operation of the content, in accordancewith the usage conditions held; and operating means for operating thecontent if it has been determined that the operation of the content ispermitted.

[0023] The information processing device may further comprise userauthentication means for authenticating a user of the informationprocessing device.

[0024] The information processing device may further comprise secondtransmission control means for controlling the transmission of a contentoperation request to the second information providing apparatus.

[0025] An information processing method according this inventioncomprises: a holding step of holding the usage conditions of content andthe information associated with the content; a first updating step ofupdating the usage conditions and the information, held in the holdingmeans, in accordance with the operation of the content if the contenthave been operated; an apparatus authentication step of authenticatingan information providing apparatus though a transmission path; atransmission control step of controlling the transmission of the usageconditions and the information to the information providing apparatuswhen the content are operated; a reception control step of controllingthe reception of the usage conditions and the information associatedwith the content, which have been transmitted from the informationproviding apparatus; a second updating step of updating the usageconditions and the information, both held, on the basis of the usageconditions and the information which have been received; and a displaycontrol step of controlling the displaying of the information.

[0026] A recording medium according this invention records a programwhich describes: a holding step of holding the usage conditions ofcontent and the information associated with the content; a firstupdating step of updating the usage conditions and the information, heldin the holding means, in accordance with the operation of the content ifthe content have been operated; an apparatus authentication step ofauthenticating an information providing apparatus though a transmissionpath; a transmission control step of controlling the transmission of theusage conditions and the information to the information providingapparatus when the content are operated; a reception control step ofcontrolling the reception of the usage conditions and the informationassociated with the content, which have been transmitted from theinformation providing apparatus; a second updating step of updating theusage conditions and the information, both held, on the basis of theusage conditions and the information which have been received; and adisplay control step of controlling the displaying of the information.

[0027] In the information providing apparatus, information providingmethod and recording medium according to the invention, an informationprocessing device is authenticated though the transmission path. Theusage conditions of the content and the information associated with thecontent are held. The reception of the usage conditions of content andthe information associated with the content, all transmitted from theinformation processing device, is controlled. The usage conditions andthe information, both held, are updated based on the usage conditionsand the information received.

[0028] In the information processing device, information processingmethod and recording medium according to the invention, the usageconditions of content and the information associated with the contentare held. When the content are operated, the usage conditions and theinformation, all held are updated in accordance with the operation ofthe content. An information providing apparatus is authenticated throughthe transmission path. The transmission of the usage conditions and theinformation associated with the content, to the information providingapparatus, is controlled when the content is operated. The reception ofthe usage conditions and the information associated with the content,transmitted from the information providing apparatus, is controlled. Theusage conditions and the information, all held, are updated based on theusage conditions and the information received.

BRIEF DESCRIPTION OF THE DRAWINGS

[0029]FIG. 1 is a diagram showing a content display system according toan embodiment of the present invention;

[0030]FIG. 2 is a diagram depicting the configuration of a server 201;

[0031]FIG. 3 is a diagram illustrating the function of the server 201;

[0032]FIG. 4 is diagram showing an image that a display function 252makes a display section 26 display;

[0033]FIG. 5 is a diagram illustrating an example of content, which acontent database 224 records;

[0034]FIG. 6 is a flowchart explaining how the content is displayed;

[0035]FIG. 7 is a flowchart explaining an initialization process;

[0036]FIG. 8 is a flowchart explaining how the content is reproduced;

[0037]FIG. 9 is a flowchart describing the process of moving thecontent;

[0038]FIG. 10 is a flowchart explaining the process of moving thecontent;

[0039]FIG. 11 is a flowchart describing a process of updating thecontent data;

[0040]FIG. 12 is a flowchart describing how to terminate the process;

[0041]FIG. 13 is a diagram illustrating a server 201 according toanother embodiment;

[0042]FIG. 14 is diagram showing an image that a display function 111makes the display section 26 display;

[0043]FIG. 15 is a diagram illustrating an example of content, which acontent database 102 records;

[0044]FIG. 16 is a flowchart explaining an initialization process;

[0045]FIG. 17 is a flowchart describing a process of updating thecontent data;

[0046]FIG. 18 is a flowchart describing how to terminate the process;

[0047]FIG. 19 is a diagram showing a content display system according toanother embodiment of the present invention;

[0048]FIG. 20 is a diagram for explaining the function of a server 201;

[0049]FIG. 21 is a diagram describing the function of a personalcomputer 204;

[0050]FIG. 22 is a diagram illustrating an example of the content data;

[0051]FIG. 23 is an image the personal computer 204 displays;

[0052]FIG. 24 is another image the personal computer 204 displays;

[0053]FIG. 25 is a diagram depicting another example of the contentdata;

[0054]FIG. 26 is another image the personal computer 204 displays;

[0055]FIG. 27 is a flowchart explaining the process of displaying thecontent data;

[0056]FIG. 28 is a flowchart describing the process of connecting amusical instrument;

[0057]FIG. 29 is a flowchart describing the process of moving thecontent;

[0058]FIG. 30 is another flowchart explaining the process of moving thecontent;

[0059]FIG. 31 is a flowchart describing the process of distributing thecontent data; and

[0060]FIG. 32 is a flowchart explaining the process of disconnecting themusical instrument.

BEST MODE FOR CARRYING OUT THE INVENTION

[0061] This invention will be described in further detail by way ofexample with reference to the accompanying drawings. Now, referring toFIG.1, there is shown one embodiment of a content display systemassociated with the present invention. A personal computer 1 isconnected to a PDA (Personal Digital Assistant) 2 via a network 3compliant with the IEEE (Institute of Electrical and ElectronicEngineers) 1394 or constituted by a USB (Universal Serial Bus) forexample.

[0062] The personal computer 1 records content such as music or movingor still image along with its additional information (for example,content name, content recording date, and content copyright holder), itsusage conditions (for example, the number of time the content can bereproduced, the data indicating whether the content can be moved or notor copied or not, and the number of times the content can be checkedout) and a content key. Content is encrypted by DES (Data EncryptionStandard) for example.

[0063] On the basis of a user HD or a password stored in advance, thepersonal computer 1 authenticates its user. By use of an authenticationkey for example stored in advance, the personal computer 1 authenticatesthe PDA 2 via a network 3.

[0064] The personal computer 1 receives the additional information andusage conditions of a particular piece of content from the PDA 2 via thenetwork 3 and displays the received additional information and usageconditions.

[0065] The personal computer 1 sends the additional information andusage conditions of the content stored in itself to the PDA 2 via thenetwork 3.

[0066] On the basis of the usage conditions of the content stored initself or the usage conditions (recorded in the personal computer 1) ofthe content stored in the PDA 2, the personal computer 1 moves or copiesthe content stored in itself or the PDA 2 as instructed by the user.

[0067] On the basis of the content usage conditions of the contentstored in itself, the personal computer 1 decodes the content stored initself and reproduces the decoded content as instructed by the user.

[0068] The usage conditions includes content reproduction, movement, andcopy conditions and authorized users.

[0069] The PDA 2 stores content along with its additional information,usage conditions, and content key.

[0070] The PDA 2 authenticates the user of the PDA 2. The PDA 2authenticates the personal computer 1 via the network 3.

[0071] The PDA 2 receives the additional information and usageconditions of the content stored in the personal computer 1 therefromvia the network 3 and displays the received additional information andusage conditions.

[0072] The PDA 2 sends the additional information and usage conditionsof the content stored in itself to the personal computer 1 via thenetwork 3.

[0073] On the basis of the usage conditions of the content stored initself or the usage conditions (stored in the PDA 2) of the contentrecorded in the personal computer 1, the PDA 2 moves or copies thecontent recorded in the personal computer 1 or the PDA 2 as instructedby the user.

[0074] On the basis of the usage conditions of the content stored initself, the PDA 2 reproduces the content stored in itself as instructedby the user.

[0075]FIG. 2 shows an exemplary configuration of the personal computer1. A CPU (Central Processing Unit) 21 executes various programs storedin a ROM (Read Only Memory) 22 or a RAM (Random Access Memory) 23 toimplement various capabilities to be described later with reference toFIG. 3. The ROM 22, constituted by an EEPROM (Electrically ErasableProgrammable Read Only Memory) or a flash memory for example, generallystores basically fixed data among the programs and computationalparameters to be used by the CPU 21. The RAM 23, constituted by a DRAM(Dynamic RAM) for example, stores programs to be used in the executionby the CPU 21 and parameters which vary from time to time in theexecution of these programs.

[0076] An input section 25, constituted by a mouse or an input key forexample, is operated by the user when inputting various commands intothe CPU 21. A display section 26, constituted by a liquid crystaldisplay device for example, displays various information in text orimage. An audio reproducing section 27 reproduces the audio datacontained in the content supplied from a communication section 28 or theaudio data contained in the content recorded in a recording section 29,outputting sound.

[0077] The communication section 28 stores the data (for example, acontent movement request) supplied from the CPU 21 into predeterminedpackets via the network 3 and sends the resultant packet to the PDA 2.Also, the communication section 28 outputs the data (a piece of contentfor example) or a program stored the packets received from the PDA 2 tothe CPU 21, the RAM 23, or the recording section 29.

[0078] The recording section 29, constituted by a hard disc drive forexample, records a particular piece of content along with its additionalinformation, usage conditions, and content key. The recording section 29supplies the content recorded therein along with its additionalinformation, usage conditions, and content key to the CPU 21 or the RAM23.

[0079] A drive 30 reads the data or programs from a magnetic disc 51, anoptical disc 52, a magneto-optical disc 53, or a semiconductor memory 54and supplies the data or programs to the ROM 22 or the RAM 23 via a bus24.

[0080] The above-mentioned components, the CPU 21 through the drive 30,are interconnected by the bus 24.

[0081] The PDA 2 has a configuration similar to that of the personalcomputer 1 and therefore need not be described.

[0082] FIG.3 describes the capabilities provided by the personalcomputer 1 to be implemented by the CPU 21 by executing respectiveprograms. The personal computer 1 has an authentication capability 71, acontent display capability 72, a content reproduction capability 73, acontent management capability 74, a copyright management capability 75,a content database 76, and a communication capability 77.

[0083] The authentication capability 71 incorporates a user database 81.The user database 81 records the authentication information of the user(the user ID or password for example for user identification). Theauthentication capability 71 authenticates the user by use of the dataabout user operation supplied from the input section 25 and the userauthentication information recorded in the user database 81.

[0084] The authentication capability 71 stores an authentication key forexample necessary for authentication processing and authenticates thePDA 2 via the network 3 by a challenge and response method for exampleon the basis of the data received by the communication section 28 andthe data sent by the communication section 28 under the control of thecommunication capability 77.

[0085] The content display capability 72 has a display capability 82 andan operation instructing capability 83. The display capability 82displays, in a tree structure for example, the additional information ofcontent for example included in the content information recorded in thecontent database 76 onto the display section 26. The content informationincludes device IDs for device identification, content file names(including a so-called path name), content IDs, and content additionalinformation and usage conditions).

[0086]FIG. 4 shows an exemplary screen displayed by the displaycapability 82 on the display section 26.

[0087] In the exemplary screen shown in FIG.4, the personal computer 1holds content “pops1” and content “pops2” in directory “¥MUSIC ¥POPS”and the PDA 2 holds content “rock1” and content “rock2” in directory“¥AUDIO ¥ROCK.”

[0088] When any of the capabilities shown in FIG. 3 operates as adaemon, the display capability 82 does not display content-associatedinformation on the display section 26.

[0089] The operation instructing capability 83 instructs the contentreproduction capability 73 to reproduce a particular piece of contentwhen the predetermine data associated with a user operation such as aclick on the screen is supplied from the input section 25 and causes thedisplay capability 82 to update the display.

[0090] When the predetermined data associated with a user operation suchas drag and drop are supplied from the input section 25, the operationinstructing capability 83 instructs the content management capability 74to move or copy a particular piece of content and causes the displaycapability 82 to update the display.

[0091] When requested by the user for updating content information, theoperation instructing capability 83 instructs the content managementcapability 74 to update the content information and causes the displaycapability 82 to update the display.

[0092] When requested by the user for ending a currently executedprogram, the operation instructing capability 83instructs the contentmanagement capability 74 to discard the content information associatedwith the content stored in the PDA 2, thereby ending the program.

[0093] On the basis of an instruction given by the operation instructingcapability 83, the content reproduction capability 73 decodes thecontent stored in the content database 76 and reproduces the decodedcontent. The content reproduction capability 73 causes the copyrightmanagement capability 75 to update the usage conditions recorded in thecontent database 76.

[0094] The content management capability 74 writes to the contentdatabase 76 the content information about the content stored in the PDA2 received by the communication section 28 controlled by thecommunication capability 77.

[0095] The content management capability 74 causes the communicationsection 28 controlled by the communication capability 77 to send thecontent information about the content stored in the content database 76to the PDA 2 via the network 3.

[0096] When instructed by the operation instructing capability 83 tomove or copy a particular piece of content in the content database 76,the content management capability 74 inquires the copyright managementcapability 75 whether the movement or copy of the content is allowed. Ifthe movement or copy is found allowed on the basis of the usageconditions recorded in the content database 76, the content managementcapability 74 moves or copies the content to the content database 76.The content management capability 74 instructs the copyright managementcapability 75 to update the usage conditions on both the source anddestination of the moved content.

[0097] If the movement or copy is found not allowed by the copyrightmanagement capability 75, the content management capability 74 does notmove or copy the content.

[0098] When instructed by the operation instructing capability 83 tomove or copy content from the PDA 2 to the content database 76, thecontent management capability 74 inquires the copyright managementcapability 75 whether the movement or copy of the content is allowed ornot. If the movement or copy is found allowed, the content managementcapability 74 causes the communication section 28 under the control ofthe communication capability 77 to send a content request. The contentrequest to be sent from the communication section 28 to the PDA 2contains content ID, file name including path name, and movement or copyinstruction.

[0099] If the movement or copy is found not allowed by the copyrightmanagement capability 75, the content management capability 74 does notcause the communication section 28 to send the content request.

[0100] The content management capability 74 causes the communicationsection 28 to receive the content supplied by the PDA 2 and record thereceived content to the content database 76 and instructs the copyrightmanagement capability 75 to update the usage conditions of the receivedcontent. At this moment, the content database 76 relates a new contentID to the recorded content.

[0101] Receiving from the operation instructing capability 83 aninstruction for moving or copying content from the content database 76to the PDA 2, the content management capability 74 inquires thecopyright management capability 75 whether the movement or copy of thecontent is allowed or not. If the movement or copy is found allowed, thecontent management capability 74 causes the communication section 28controlled by the communication capability 77 to send the content alongwith its content ID, file name of the movement (or copy) destinationincluding path name to the PDA 2.

[0102] If the movement or copy is found not allowed by the copyrightmanagement capability 75, then the content management capability 74 doesnot cause the communication section 28 to send the content.

[0103] When the communication section 28 has received a contentreception acknowledgment from the PDA 2, the content managementcapability 74 instructs the copyright management capability 75 to updatethe usage conditions of the transmitted content. For content movement,when the communication section 28 receives a content receptionacknowledgment from the PDA 2, the content management capability 74 setsthe usage condition so as to prevent the moved content from being usedor causes the content database 76 to delete the moved content.

[0104] When the communication capability 77 has received from the PDA 2a content movement or copy request for moving or copying content fromthe content database 76 to the PDA 2, the content management capability74 inquires the copyright management capability 75 whether the movementor copy of the content is allowed or not. If the movement or copy isfound allowed, then the content management capability 74 causes thecommunication section 28 controlled by the communication capability 77to send the content along with its content ID and its file name ofmovement (or copy) destination including path name to the PDA 2.

[0105] If the movement or copy is found not allowed by the copyrightmanagement capability 75, then the content management capability 74 doesnot cause the communication section 28 to send the content.

[0106] When the communication section 28 receives a content receptionacknowledgement from the PDA 2, the content management capability 74instructs the copyright management capability 75 to update the usageconditions of the transmitted content. For content movement, when thecommunication section 28 receives a content reception acknowledgementfrom the PDA 2, the content management capability 74 sets the usagecondition so as to prevent the moved content from being used or causesthe content database 76 to delete the moved content.

[0107] When the communication capability 77 receives from the PDA 2 thecontent to be moved or copied to the personal computer 1, the contentmanagement capability 74 inquires the copyright management capability 75whether the movement or copy of the content is allowed or not. If themovement or copy is found allowed, the content management capability 74causes the content database 76 to record the received content andinstructs the copyright management capability 75 to update the usageconditions of the received content. The content database 76 relates anew content ID to the recorded content.

[0108] If the movement or copy is found not allowed, then the contentmanagement capability 74 discards the received content.

[0109] When the personal computer 1 is disconnected from the network 3,the content management capability 74 discards the content informationassociated with the content recorded in the content database 76 andstored in the PDA 2.

[0110] On the basis of the content usage conditions, the copyrightmanagement capability 75 enables or disables the reproduction, movement,or copy of the content recorded in the content database 76 and, if thecontent has been reproduced, moved, or copied, causes the contentdatabase 76 to update the usage conditions of the content. On the basisof the content usage conditions, the copyright management capability 75enables or disables the movement or copy of the content stored in thePDA 2 and, if the content has been moved or copied, causes the contentdatabase 76 to update the usage conditions of the content.

[0111] The content database 76 records, in a directory structure, thecontent and its content ID, additional information, usage conditions andcontent key as one file. When the personal computer 1 is connected tothe PDA 2 via the network 3, the content database 76 records the contentinformation associated with the content received from the PDA 2 andrecorded in the PDA 2.

[0112] FIG.5 shows one example of the content information recorded inthe content database 76. A piece of content of which content ID is “AAA”is recorded on a device (for example, the personal computer 1) of whichdevice ID is “DDD,” the name of the content being “111” and itsrecording date being “YYMMDD.” For the piece of content of which contentID is “AAA,” its authorized user is “UUU,” permitted copy count is 0,permitted movement count is 3, and permitted reproduction count is 10.The piece of content of which content ID is “AAA” is stored in a file ofwhich file name is “audiol” recorded in a directory indicated by path“¥ROOT 536 AUDIO” on the device of which device ID is “DDD.”

[0113] A piece of content of which content ID is “BBB” is recorded on adevice (for example, the PDA 2) of which device ID is “ddd,” name of thecontent being “222” and its recording date being “yymmdd.” For the pieceof content of which content ID is “BBB,” its authorized user is “uuu,”permitted copy count is 0, permitted movement count is 3, and permittedreproduction count is 10. The piece of content of which content ID is“BBB” is stored in a file of which file name is audio2 recorded in adirectory indicated by path ¥ROOT ¥AUDIO on the device of which deviceID is “ddd.”

[0114] The communication capability 77 controls the communicationsection 28 to cause the same to receive content or content informationfrom the PDA 2 via the network 3 and send content or content informationto the PDA 2.

[0115] It should be noted that the capabilities of the PDA 2 aregenerally the same as those of the personal computer 1 and thereforeneed not be described.

[0116] The following describes the processing to be executed by thecontent display system associated with the present invention. In whatfollows, the processing in which the personal computer 1 displayscontent will be described.

[0117] The processing of displaying content by the personal computer 1will be described with reference to the flowchart shown in FIG. 6. Instep S11, the personal computer 1 executes an initialization process.The details of this process will be described later with reference tothe flowchart shown in FIG. 7.

[0118] In step S12, the operation instructing capability 83 of thecontent display capability 72 determines on the basis of a signalsupplied from the input section 25 whether the reproduction of contenthas been requested or not. If the reproduction is found requested, thenthe process goes to step S13, in which the operation instructingcapability 83 causes the content reproduction capability 73 to decodethe encrypted content by the content key and execute a process forreproducing the decoded content. When the reproduction process iscompleted, the process returns to step S12 to repeat the decisionprocess. The details of the reproduction process will be described laterwith reference to the flowchart shown in FIG. 8.

[0119] If, in step S12, the reproduction is found not requested, thenthe procedure goes to step S14, in which the operation instructingcapability 83 of the content display capability 72 determines on thebasis of a signal supplied from the input section 25 corresponding to adrag and drop operation for example or the data supplied from thecommunication capability 77 (for example, corresponding to a contentmovement request by the PDA 2) whether a content movement request hasbeen made. If a content movement request is found, then the proceduregoes to step S15, in which the content management capability 74 executesa content movement process. When the content movement process iscompleted, the procedure returns to step S12 to repeat the decisionprocess. The details of the movement process will be described laterwith reference to the flowcharts shown in FIGS. 9 and 10.

[0120] If, in step S14, no content movement request is found, then theprocedure goes to step S16, in which the operation instructingcapability 83 of the content display capability 72 determines on thebasis of a signal supplied from the input section 25 or the datasupplied from the communication capability 77 whether a contentinformation update request has been made or not. If a contentinformation update request is found, then the procedure goes to stepS17, in which the content management capability 74 executes a contentinformation update process. When the content information update processis completed, the procedure returns to step S12 to repeat the decisionprocess. The details of the content information update process will bedescribed later with reference to the flowchart shown in FIG. 11.

[0121] If, in step S16, no content information update request is found,then the process goes to step S18, in which the operation instructingcapability 83 of the content display capability 72 determines on thebasis of a signal supplied from the input section 25 whether the displayprocessing is to be ended or not. If the display processing is not to beended, the process returns to step S12 to repeat the decision process.

[0122] If, in step S18, the display processing is to be ended, then theprocess goes to step S19, in which the operation instructing capability83 causes the content management capability 74 to execute the endprocessing, upon which the display processing comes to an end. Thedetails of the end processing will be described later with reference tothe flowchart shown in FIG. 12.

[0123] As described, the personal computer 1 displays the contentinformation corresponding to the content stored in the personal computer1 itself and the content stored in the PDA 2. At the same time, thepersonal computer 1 can move or copy the content stored in itself or thecontent stored in the PDA 2.

[0124] The content display processing by the PDA 2 is generally the sameas that by the personal computer 1 and therefore need not be described.

[0125] The following describes the details of the initializationprocessing of step S11 shown in FIG. 6 with reference to the flowchartshown in FIG. 7. In step S1101, the authentication capability 71executes a process of authenticating the PDA 2 by use of a challenge andresponse method for example. If, in step S1101, the PDA 2 is found notcompliant, the processing comes to an end without updating the contentinformation.

[0126] In step S2101, the PDA 2 executes a process of authenticating thepersonal computer 1. If, in step S2101, the personal computer is foundnot compliant, then the processing comes to an end without updating thecontent information.

[0127] If, in step S1101, the PDA 2 is found compliant, authenticatingthe PDA 2, and if, in step S2101, the personal computer 1 is foundcompliant, authenticating the personal computer 1, then the proceduregoes to step S1102, in which the authentication capability 71authenticates the user on the basis of the data supplied from the inputsection 25 or the user authentication information recorded in the userdatabase 81. If, in step S1102, the user is found not authorized, thenthe processing comes to an end without updating the content information.

[0128] If, in step S1102, the user is found authorized, authenticatingthe user, then the procedure goes to step S1103, in which the contentmanagement capability 74 reads the content information associated withthe content recorded by itself from the content database 76 and causesthe communication capability 77 to send the retrieved content to the PDA2 via the network 3.

[0129] In step S2102, the PDA 2 receives the content information sent bythe personal computer 1. In step S2103, a content management capability,not shown, of the PDA 2 updates the stored content information on thebasis of the received content information. Namely, the PDA 2 adds thecontent information associated with the content stored in the personalcomputer 1 to the content information recorded in the PDA2.

[0130] In step S2104, the content management capability of the PDA 2sends the content information associated with the content stored initself to the personal computer 1 via the network 3.

[0131] In step S1104, the communication capability 77 receives thecontent information sent from the PDA 2. In step S1105, the contentmanagement capability 74 causes the content database 76 to update thecontent information. Namely, the content database 76 records the contentinformation received in step S1104 and associated with the contentstored in the PDA 2.

[0132] In step S1106, the display capability 82 displays on the displaysection 26 the content information associated with the content stored inthe personal computer 1 and the content information associated with thecontent stored in the PDA 2, upon which the processing comes to an end.

[0133] Thus, after the cross-authentication process, the personalcomputer 1 and the PDA 2 exchange the content information to update it.The personal computer 1 can display on the display section 26 thecontent information associated with the content stored in itself and thecontent information associated with the content stored in the PDA 2.

[0134] The following describes the details of the reproductionprocessing of step S13 shown in FIG. 6 with reference to the flowchartof FIG. 8. In step S1201, the copyright management capability 75 checksthe usage conditions of the content recorded in the content database 76and requested for reproduction. If the usage conditions do not allowreproduction, the processing comes to an end without reproducing thecontent.

[0135] If the usage conditions allow reproduction, the procedure goes tostep S1202, in which the content reproduction capability 73 decrypts theencrypted content with the content key to reproduce the decryptedcontent. In step S1203, the copyright management capability 75 updatesthe usage conditions of the reproduced content (for example,decrementing the reproduction count by 1) to end the processing.

[0136] Thus, the personal computer 1 reproduces content when itsreproduction is allowed on the basis of its usage conditions.

[0137] The following describes the details of moving content from thePDA 2 to the personal computer 1 described in step S15 of FIG. 6, withreference to the flowchart shown in FIG. 9. In step S1301, the copyrightmanagement capability 75 checks the usage conditions for the contentrequested for movement stored in the content database 76. The usageconditions for the content stored in the PDA 2 are recorded in thecontent database 76 by the initialization process.

[0138] If the usage conditions of the content requested for movement donot allow movement, then the processing comes to an end without movingthe content.

[0139] If the usage conditions of the content requested for movementpermit movement, then the procedure goes to step S1302, in which thecontent management capability 74 causes the communication capability 77to send a content movement request to the PDA 2 via the network 3.

[0140] In step S2301, the PDA 2 receives the content movement request.In step S2302, a copyright management capability, not shown, of the PDA2 checks the usage conditions (stored in the PDA 2) of the contentrequested for movement. If the usage conditions of the content requestedfor movement permit movement, then the processing comes to an endwithout moving the content.

[0141] If the usage conditions of the content requested for movementpermit movement, then the procedure goes to step S2303, in which the PDA2 sends the content requested for movement to the personal computer 1via the network 3.

[0142] In step S1303, the communication capability 77 of the personalcomputer 1 causes the communication section 28 to receive the content.In step S1304, the content management capability 74 causes the contentdatabase 76 to record the received content. In step S1305, the copyrightmanagement capability 75 causes the content database 76 to update theusage conditions of the recorded content. In step S1306, the contentmanagement capability 74 causes the content database 76 to update thecontent information about the recorded content.

[0143] In step S2304, the content management capability of the PDA 2updates the usage conditions of the transmitted content. In step S2305,the content management capability of the PDA 2 updates the contentinformation about the transmitted content, upon which the processingcomes to an end.

[0144] Thus, in response to a request by the personal computer 1 on thebasis of the usage conditions, the PDA 2 can move the content recordedin it to the personal computer 1.

[0145] The following describes the details of moving content from thepersonal computer 1 to the PDA 2 described in step S15 of FIG. 6, withreference to the flowchart of FIG. 10. In step S1401, the copyrightmanagement capability 75 checks the usage conditions of the contentrequested for movement stored in the content database 76. If the usageconditions do not permit movement, then the processing comes to an endwithout moving the content.

[0146] If the usage conditions of the content requested for movementpermit movement, then the procedure goes to step S1402, in which thecontent management capability 74causes the communication capability 77to send the content to the PDA 2 via the network 3.

[0147] In step S2401, the PDA 2 receives the content. In step S2402, thecopyright management capability of the PDA 2 checks the usage conditionsof the content requested for movement. If the usage condition do notpermit movement, then the processing comes to an end by discarding thereceived content.

[0148] If the usage conditions permit movement, then the procedure goesto step S2403, in which the content database, not shown, of the PDA 2stores the received content. In step S2404, the content managementcapability of the PDA 2 sends a content reception acknowledgement to thepersonal computer 1 via the network 3.

[0149] In step S1403, the communication capability 77 of the personalcomputer 1 causes the communication section 28 to receive the contentreception acknowledgement. In step S1404, the copyright managementcapability 75 causes the content database 76 to update the usageconditions of the transmitted content. In step S1405, the contentmanagement capability 74 causes the content database 76 to update thecontent information about the transmitted content.

[0150] In step S2405, the content management capability of the PDA 2updates the usage conditions of the stored content. In step S2406, thecontent management capability of the PDA 2 updates the contentinformation about the stored content, upon which the processing comes toan end.

[0151] Thus, on the basis of the usage conditions, the personal computer1 can move the recorded content to the PDA 2.

[0152] It should be noted that content copy processing is executed ingenerally the same manner as content movement processing and thereforeneed not be described.

[0153] The following describes the details of content information updateprocessing described in step S17 of FIG. 6, with reference to theflowchart of FIG. 11. In step S1501, the content management capability74 reads the content information associated with the content recorded initself from the content database 76 and causes the communicationcapability 77 to send the retrieved content to the PDA 2 via the network3.

[0154] In step S2501, the PDA 2 receives the content informationtransmitted by the personal computer 1. In step S2502, the PDA 2 updatesthe recorded content information on the basis of the content informationassociated with the content recorded in the personal computer 1. In stepS2503, the PDA 2 sends the content information associated with thecontent stored in itself to the personal computer 1 via the network 3.

[0155] In step S1502, the communication capability 77 receives thecontent information sent from the PDA 2. In step S1503, the contentmanagement capability 74 causes the content database 76 to update thecontent information on the basis of the content information received instep S1502. In step S1504, the display capability 82 causes the displaysection 26 to display the updated content information, upon which theprocessing comes to an end.

[0156] Thus, on the basis of the content information received from thePDA 2, the personal computer 1 updates the content information recordedin the content database 76. The PDA 2 updates the content information onthe basis of the content information received from the personal computer1.

[0157] The following describes the details of the end processingdescribed in step S19 of FIG. 6, with reference to the flowchart of FIG.12. In step S1601, the content management capability 74 causes thecontent database 76 to discard the content information associated withthe content in the PDA 2 (the content information with the device IDcorresponding to the PDA 2), upon which the processing comes to an end.

[0158] Thus, when ending the content display processing, the personalcomputer 1 discards the content information associated with the contentstored in the PDA 2. Therefore, the personal computer 1 displays on thedisplay section 26 only the content information associated with thecontent stored in the devices connected to the personal computer 1.

[0159] The following describes another embodiment of the content displaysystem associated with the present invention.

[0160]FIG. 13 shows other capabilities of the personal computer 1 to berealized by the program execution by the CPU 21. With reference to FIG.13, components similar to those described with reference to FIG. 3 aredenoted by the same reference numerals and need not be described.

[0161] A content display capability 72 has a display capability 111 anda operation instructing capability 112. The display capability 111displays in a tree structure the information about the content recordedin a content database 102 onto a display section 26.

[0162] On the basis of a connection status flag recorded in the contentdatabase 102, the display section 111 displays the content informationin different colors or shapes depending on whether the device storingthe content indicated by the content information is connected or not.

[0163]FIG. 14 shows an exemplary screen which is displayed by thedisplay capability 111 onto the display section 26.

[0164] The display example shown in FIG. 14 indicates that the personalcomputer 1 is holding content “pops1” and content “pops2” in directory“¥MUSIC ¥POPS” and the PDA 2 connected to the personal computer 1 isholding content “rock1” and “rock2” in directory “¥AUDIO ¥ROCK.” Thedisplay example shown in FIG. 14 indicates that a device DDD (forexample, a portable personal computer not shown) not connected to thepersonal computer 1 is holding content “audio1” and content “audio2” indirectory “¥ROOT ¥AUDIO.”

[0165] As shown in FIG. 14, the display capability 111 displays in bluethe content information about the content stored in a device connectedto the personal computer 1 and in red the content information about thecontent stored in a device not connected to the personal computer 1.

[0166] Consequently, the user of the personal computer 1 can instantlyknow whether the device storing a desired piece of content is connectedto the personal computer 1.

[0167] It should be noted that the display capability 111 may display,in a different manner, the background shapes of the content informationabout the content stored in a device connected to the personal computer1 and of the content information about the content stored in a devicenot connected to the personal computer 1. For example, the displaycapability 111 displays, in a square, the background of the contentinformation about the content stored in a device connected to thepersonal computer 1 and, in a circle, the background of the contentinformation about the content stored in a device not connected to thepersonal computer 1.

[0168] If the capabilities shown in FIG. 13 operate as a daemon, thedisplay capability 111 does not display the information about contentonto the display section 26.

[0169] When predetermined data have been supplied from the input section25 as a result of an operation made by the user such as clicking on thescreen, the operation instructing capability 112 instructs a contentreproduction capability 73 to reproduce the content and causes thedisplay capability 111 to update the display. When predetermined datahave been supplied from the input section 25 as a result of an operationmade by the user such as a drag and drop, the operation instructingcapability 112 instructs a content management capability 101 to move orcopy the content and causes the display capability 111 to update thedisplay.

[0170] When requested by the user for updating content information, theoperation instructing capability 112 instructs the content managementcapability 101 to update the content information and causes the displaycapability 111 to update the display.

[0171] When the PDA 2 is connected to the personal computer 1, theoperation instructing capability 112 causes the content managementcapability 101 to update the connection status flag corresponding to thecontent information of content stored in the PDA 2. When the PDA 2 isdisconnected from the personal computer 1, the operation instructingcapability 112 causes the content management capability 101 to updatethe connection status flag corresponding to the content information ofcontent stored in the PDA 2.

[0172] When requested by the user for ending the content displayprocessing, the operation instructing capability 112 causes the contentmanagement capability 101 to update the connection status flagcorresponding to the content information about content stored in the PDA2, thereby ending the program.

[0173] When a communication section 28 controlled by a communicationcapability 77 has received, from the PDA 2, the content informationabout the content stored in the PDA 2, the content management capability101 causes the content database 102 to discard the content informationabout the content stored in the PDA 2 and write the received contentinformation.

[0174] The content management capability 101 causes the communicationsection 28 controlled by the communication capability 77 to send thecontent information about the content stored in the content database 102to the PDA 2.

[0175] When the personal computer 1 is connected to the PDA 2 via thenetwork 3, the content management capability 101 rewrites to “true” aconnection status flag included in the content information about thecontent recorded in the content database 102 and stored in the PDA 2,“true” being indicative of that the personal computer 1 is connected tothe PDA 2.

[0176] When the personal computer 1 is disconnected from the PDA 2 viathe network 3, the content management capability 101 rewrites to “false”the connection status flag included in the content information about thecontent recorded in the content database 102 and stored in the PDA 2,“false” being indicative of that the personal computer 1 is disconnectedfrom the PDA 2.

[0177] When instructed by the operation instructing capability 112 tomove or copy content inside the content database 102, the contentmanagement capability 101 inquires the copyright management capability75 whether the content movement or copy is permitted or not. If thecontent movement is found permitted, the content management capability101 causes the content database 102 to move or copy content andinstructs the copyright management capability 75 to update the usageconditions of both the source and the destination.

[0178] If the content movement or copy is found not permitted, thecontent management capability 101 does not execute the content movementor copy processing.

[0179] When instructed by the operation instructing capability 112 tomove or copy content from PDA 2 to the content database 102, the contentmanagement capability 101 inquires the copyright management capability75 whether content movement or copy is permitted or not. If the contentmovement or copy is found permitted, the content management capability101 causes the communication section 28 controlled by the communicationcapability 77 to send a content request. The content request to be sentfrom the communication section 28 to the PDA 2 includes content ID, filename including path name, and movement or copy operation instruction.

[0180] If the content movement or copy is found not permitted by thecopyright management capability 75, the content management capability101 sends no content request.

[0181] The content management capability 101 causes the communicationsection 28 to receive the content sent by the PDA 2 and causes thecontent database 102 to record the received content and instructs thecopyright management capability 75 to update the usage conditions of thereceived content. The content database 102 relates a new content ID tothe recorded content.

[0182] Instructed by the operation instructing capability 102 to move orcopy content from the content database 102 to the PDA 2, the contentmanagement capability 101 inquires the copyright management capability75 whether content movement or copy is permitted or not. If the contentmovement or copy is found permitted, the content management capability101 causes the communication section 28 controlled by the communicationcapability 77 to send the content along with its content ID and themovement (or copy) destination file name including path name to the PDA2.

[0183] If the content movement or copy is found not permitted, then thecontent management capability 101 sends no content.

[0184] When, after the content has been sent, the communication section28 receives a content reception acknowledgement from the PDA 2, thecontent management capability 101 instructs the copyright managementcapability 75 to update the usage conditions of the transmitted content.

[0185] For content movement processing, the content managementcapability 101 causes the content database 102 to delete the transmittedcontent.

[0186] Requested by the PDA 2 for moving or copying content from thecontent database 102 to the PDA 2, the content management capability 101inquires the copyright management capability 75 whether content movementor copy is permitted or not. If the content movement or copy is foundpermitted, the content management capability 101 causes thecommunication section 28 controlled by the communication capability 77to send the content along with its content ID and the movement (or copy)destination file name including path name to the PDA 2.

[0187] If the content movement or copy is found not permitted, thecontent management capability 101 does not send the content.

[0188] When, after the content has been sent, the communication section28 receives a content reception acknowledgement from the PDA 2, thecontent management capability 101 instructs the copyright managementcapability 75 to update the usage conditions of the transmitted content.When a content movement request has been made, the content managementcapability 101 causes the content database 102 to delete the movedcontent.

[0189] Receiving the content to be moved or copied from the PDA 2 to thepersonal computer 1, the content management capability 101 inquires thecopyright management capability 75 whether content movement or copy ispermitted or not. If the content movement or copy is found permitted,the content management capability 101 causes the content database 102 torecord the received content and instructs the copyright managementcapability 75 to update the usage conditions of the received content.The content database 102 relates a new content ID to the recordedcontent.

[0190] If the content movement or copy is found not permitted, thecontent management capability 101 discards the received content.

[0191] The content database 102 records, in a directory structure, thecontent, its content ID, device ID, connection status flag, additionalinformation, usage conditions, and content key as one file.

[0192] The connection status flag indicates whether a device identifiedby the corresponding device ID is connected to the personal computer 1or not. The “true” connection status flag indicates that a deviceidentified by the corresponding device ID is connected to the personalcomputer 1. The “false” connection status flag indicates that a deviceidentified by the corresponding device ID is not connected to thepersonal computer 1.

[0193] When the personal computer 1 is connected to the PDA 2 via thenetwork 3 and when the content information about the content stored inthe PDA 2 is received, the content database 102 discards the contentinformation for the PDA 2 stored so far and records the receivedcontent.

[0194]FIG. 15 shows one example of the content information stored in thecontent database 102. A piece of content of which content ID is “AAA” isrecorded on a device of which device ID is “DDD,” the name of thecontent being “111” and its recording date being “YYMMDD.” Because theconnection status flag corresponding to the device of which device ID is“DDD” is “false,” the device of which device ID is “DDD” is notconnected to the personal computer 1.

[0195] For the piece of content of which content ID is “AAA,” itsauthorized user is “UUU,” permitted copy count is 0, permitted movementcount is 3, and permitted reproduction count is 10. The piece of contentof which content ID is “AAA” is stored in a file of which file name isaudio1 recorded in a directory indicated by path ¥ROOT ¥AUDIO ¥ on thedevice of which device ID is “DDD.”

[0196] A piece of content of which content ID is “BBB” is recorded on adevice of which device ID is “DDD,” name of the content being “222” andits recording date being “yymmdd.” For the piece of content of whichcontent ID is “BBB,” its authorized user is “uuu,” permitted copy countis 0, permitted movement count is 3, and permitted reproduction count is10. The piece of content of which content ID is “BBB” is stored in afile of which file name is audio2 recorded in a directory indicated bypath ¥ROOT ¥AUDIO ¥ on the device of which device ID is “DDD.”

[0197] The following describes the processing to be executed by thecontent display system having the other capabilities shown in FIG. 13.

[0198] The content display processing is generally the same as thatdescribed with reference to FIG. 6 and therefore need not be described.

[0199] The following describes the details of the initializationprocessing with reference to the flowchart shown in FIG. 16. Theprocesses of steps S1701 through S1704 are generally the same as thoseof steps S1101 through S1104 and therefore need not be described.

[0200] In step S1705, the content management capability 101 causes thecontent database 102 to discard the content information about contentstored in the PDA 2. In step S1706, the content management capability101 causes the content database 102 to update the content information onthe basis of the content information received in step S1704. Namely, thecontent database 102 records the received content information about thecontent stored in the PDA 2 and sets the connection status flagcorresponding to the device ID of the PDA 2 to “true.”

[0201] In step S1707, the display capability 82 displays the updatedcontent information onto the display section 26, upon which the contentdisplay processing comes to an end. The display capability 82 displays,in different images, the content information for which connection statusflag is “true” and the content information for which connection statusflag is “false” ; for example, the content information in blue for whichconnection status is “true” and the content information in red for whichconnection status is “false.”

[0202] Thus, the personal computer 1 can update the content informationabout the content stored in the PDA 2 and, at the same time, update theconnection status flag. The personal computer 1 displays the contentinformation in a color or a shape depending on the setting of theconnection status flag.

[0203] The content reproduction processing is generally the same as thatdescribed with reference to FIG. 8 and therefore need not be described.

[0204] The content movement processing is generally the same as thatdescribed with reference to FIG. 9 or 10 and therefore need not bedescribed.

[0205] The following describes content information update processingwith reference to the flowchart shown in FIG. 17. The processes of stepsS1801 through S1802 are generally the same as those of steps S1501through S1502 of FIG. 11 and therefore need not be described.

[0206] In step S1803, the content management capability 101 causes thecontent database 102 to discard the content information about thecontent stored in the PDA 2. In step S1804, the content managementcapability 101 causes the content database 102 to update the contentinformation on the basis of the content information received in stepS1802.

[0207] In step S1805, the display capability 82 causes the displaysection 26 to display the updated content information, upon which thecontent information update processing comes to an end.

[0208] Thus, the personal computer 1 updates the content information anddisplays the updated content information.

[0209] The following describes end processing with reference to theflowchart shown in FIG. 18. In step S1901, the content managementcapability 74 causes the content database 76 to set to “false” theconnection status flag for the content information associated with thecontent stored in the PDA 2, upon which the content display processingcomes to an end.

[0210] Thus, when ending the content display processing, the personalcomputer 1 updates the connection status flag contained in the contentinformation about the content stored in the PDA 2.

[0211] In the above description, the personal computer 1 is connected tothe PDA 2 via the network 3. It will be apparent to those skilled in theart that the personal computer 1 may also be connected to a mobiletelephone, a PHS (Personal Handyphone System) terminal, a digital stillcamera, a digital video camera, a vehicle navigation device, atelevision receiver, a radio receiver, or a portable device for exampleto execute the above-mentioned various processing operations.

[0212] In the above description, the personal computer 1 is connected tothe PDA 2 via the network 3. It will be apparent to those skilled in theart that the personal computer 1 may also be connected to the PDA 2 viapublic switched phone line, mobile telephone communication line, PHS,the Internet, Bluetooth communication, digital satellite broadcasting,or other wired or wireless communication media.

[0213] The content to be recorded or stored in the personal computer 1or the PDA 2 is not restricted to music and image; the content may alsobe audio data, text data, programs, or data for executing programs.

[0214] In addition to DES, the above-mentioned content may be encryptedby another block encryption of common key encryption, stream encryption,or public key encryption.

[0215]FIG. 19 is a diagram that shows a content display system accordingto another embodiment of the present invention.

[0216] A server 201 is connected by a network 202 to a PDA 203 and apersonal computer 204.

[0217] The network 202 is either a local area network or the Internet.The local area network may be a network defined by IEEE 1394 or anetwork defined by IEEE 802.3.

[0218] The server 201 records content and the content information andcontent key, both corresponding to content. The content is music andimages such as moving pictures or still pictures. The content has beenencrypted by a specific system such as DES.

[0219] The server 201 records the content information about the contentthat is stored in the PDA 203, the personal computer 204 or a hard discdrive 205.

[0220] The server 201 authenticates its user in accordance with the userID or password it has already stored. Using the authentication keystored in it, the server 201 authenticates the PDA 203 or the personalcomputer 204 via the network 202.

[0221] The server 201 uses the password stored in it, thusauthenticating the user of the PDA 203 or personal computer 204 throughthe network 202.

[0222] The server 201 receives the content information about the contentstored in the PDA 203, from the PDA 203 through the network 202. Inaccordance with the content information it has received, the server 201updates the content information it has recorded.

[0223] The server 201 receives the content information recorded in thepersonal computer 204, from the personal computer 204 through thenetwork 202. In accordance with the content information it has received,the server 201 updates the content information it has recorded.

[0224] The server 201 receives the content information about the contentthat is recorded in the hard disc drive 205, from the personal computer204 through the network 202. In accordance with the content informationit has received, the server 201 updates the content information it hasrecorded.

[0225] After updating the content information about the content storedin the PDA 203, the personal computer 204 or the hard disc drive 205,the server 201 transmits the content information updated, to the PDA 203and the personal computer 204 through the network 202.

[0226] In response to a request made by the PDA 203 or the personalcomputer 204, the server 201 transfers or copies the content it records,to the PDA 203, the personal computer 204 or the hard disc drive 205, inaccordance with the content usage conditions it records.

[0227] In response to a request made by the PDA 203, the server 201transfers or copies the content recorded in the personal computer 204 orthe hard disc drive 205, to the PDA 203, in accordance with the contentusage conditions recorded in the personal computer 204 or the hard discdrive 205.

[0228] In response to a request made by the personal computer 204, theserver 201 transfers or copies the content recorded in the PDA 203 tothe personal computer 204 or the hard disc drive 205, in accordance withthe content usage conditions recorded in the PDA 203.

[0229] In response to a request made by the PDA 203, the server 201transfers or copies the content stored in the personal computer 204, tothe hard disc drive 205, in accordance with the content usage conditionsrecorded in the personal computer 204.

[0230] In response to a request made by the PDA 203, the server 201transfers or copies the content stored in the hard disc drive 205, tothe personal computer 204, in accordance with the content usageconditions recorded in the hard disc drive 205.

[0231] The PDA 203 stores the content, the content information and thecontent key.

[0232] The PAD 203 authenticates the user of the PDA 203. The PDA 203authenticates the server 201 through the network 202.

[0233] The PDA 203 receives the content information about the contentrecorded in the PDA 203, personal computer 204 or hard disc drive 205,from the server 201 through the network 202. Based on the contentinformation thus received, the PDA 203 updates the content informationit stores. The PDA 203 displays the content information about thecontent that is recorded in the PDA 203, personal computer 204 or harddisc drive 205.

[0234] The PDA 203 transmits the content information about the contentit records, to the server 201 through the network 202.

[0235] When operated by the user, the PDA 203 requests that the server201 should transfer or copy the content recorded in the server 201,personal computer 204 or hard disc drive 205.

[0236] When operated by the user, the PDA 203 reproduces the content itrecords, in accordance with the content usage conditions it stores.

[0237] The personal computer 204 stores content, along with the contentinformation about the content and a content key.

[0238] The personal computer 204 authenticates its user. Itauthenticates the server 201, too, through the network 202.

[0239] The personal computer 204 receives the content information aboutthe content recorded in the PDA 203, personal computer 204 or hard discdrive, from the server 201 through the network 202. Based on the contentinformation it has received, the personal computer 204 updates thecontent information it records.

[0240] The personal computer 204 displays the content information aboutthe content recorded in the PDA 203, personal computer 204 or hard discdrive 205.

[0241] The personal computer 204 transmits the content information aboutthe content recorded in the personal computer 204 or the hard disc drive205, to the sever 201 through the network 202.

[0242] When operated by the user, the personal computer 204 requeststhat the server 201 transfer and copy the content recorded in the server201 or the PDA 203.

[0243] When operated by the user, the personal computer 204 reproducesthe content recorded in it or the hard disc drive 205 in accordance withthe usage conditions of the content that are recorded in the personalcomputer 204 or the hard disc drive 205.

[0244] The hard disc drive 205 records the content, together with thecontent information and the content key, under the control of thepersonal computer 204.

[0245] Under the control of the personal computer 204, too, the harddisc drive 205 supplies the content, content information and contentkey, all recorded in it, to the personal computer 204.

[0246] The server 201 has the same structure as the personal computer 1shown in FIG. 2. Therefore, its structure is not described herein.

[0247] The PDA 203 has the same structure as the personal computer 1shown in FIG. 2. Therefore, the structure of the PDA 203 is notdescribed herein.

[0248] The personal computer 204 has the same structure as the personalcomputer 1 shown in FIG. 1. Therefore, the structure of the personalcomputer 204 is not described herein.

[0249]FIG. 20 is a diagram explaining the function of a server 201. Theserver 201 has an authentication function 221, a content managementfunction 222, a copyright management function 223, a content database224, and a communication function 225.

[0250] The authentication function 221 incorporates a user database 231.The user database 231 records the authentication data (i.e., user ID orpassword, for example) of the user of the server 201, PDA 203 orpersonal computer 204. The authentication function 221 authenticates theuser of the server 201, PDA 203 or personal computer 204, based on thedata about the user operation and the user authentication data. The userauthentication data is recorded in the user database 231.

[0251] The authentication function 221 stores the authentication key andthe like, which are necessary for the authentication process. Itauthenticates the PDA 203 or the personal computer 204 via the network202, by the challenge-and-response method, on the basis of, for example,the data received or transmitted under the control of the communicationfunction 225.

[0252] The content management function 222 updates the contentinformation recorded in the content database 224, on the basis of thecontent information transmitted from the PDA 203 or the personalcomputer 204 and received by the communication function 225.

[0253] The content management function 222 causes the communicationfunction 225 to transmit the content information recorded in the contentdatabase 224, to the PDA 203 or the personal computer 204 through thenetwork 202.

[0254] The content management function 222 may receive a request fortransfer of the content recorded in the server 201, from the PDA 203 orthe personal computer 204.

[0255] When the content management function 222 receives this request,it asks the copyright management function 223 if the transfer or copyingof the content has been permitted. From the usage conditions recorded inthe content database 224 the copyright management function 223determines whether the transfer or copying of the content has beenpermitted.

[0256] If the function 223 determines that the transfer or copying ofthe content has been permitted, the content management function 222causes the content database 224 to transfer or copy the content. Thecontent management function 222 instructs the copyright managementfunction 223 to update the usage conditions of both the data source anddata destination.

[0257] Assume that it is requested that the content be transferred fromthe server 201 to the PDA 203 or the personal computer 204. If thefunction 223 determines that the transfer or copying of the content hasbeen permitted, the content management function 222 reads the contentfrom the content database 224 and causes the communication function 225to transmit the content to either the PDA 203 or the personal computer204.

[0258] The function 223 may not determine that the transfer or copyingof the content has been permitted. In this case, the content managementfunction 222 will not serve to transfer or copy the content.

[0259] The communication function 225 may receive from the PDA 203 arequest for the transfer or copying of the content that are recorded inthe personal computer 204 or the hard disc drive 205. When the function225 receives this request, the content management function 222 causesthe communication function 225 to transmit the request to the personalcomputer 204 via the network 202.

[0260] When the communication function 225 receives from the personalcomputer 204 a request for the transfer or copying of the content storedin the PAD 203, the content management function 222 causes thecommunication function 225 to transmit the request to the PDA 203through the network 202.

[0261] The request for the transfer or copying of the content, which thecommunication function 225 transmits to the PDA 203 or the personalcomputer 204 contains a content ID, a file name including a path and anoperation instruction (such as the transfer or the copying).

[0262] When the communication function 225 receives the content from thePDA 203 or the personal computer 204, the content management function222 causes the function 225 to record the content into the contentdatabase 224.

[0263] When the content are transferred or copied to the PDA 203 orpersonal computer 204, the content management function 222 instructs thecontent database 224 to update the content transferred or copied to thePDA 203 or personal computer 204. When the content are transferred orcopied from the PDA 203 or personal computer 204, the communicationfunction 222 instructs the content database 224 to update the contenttransferred or copied from the PDA 203 or personal computer 204.

[0264] When the PDA 203 is disconnected from the network 202, thecontent management function 222 causes the content database 224 toupdate the content information that corresponds to the content stored inthe PDA 203.

[0265] When the personal computer 204 is disconnected from the network202, the content management function 222 causes the content database 224to update the content information that corresponds to the content storedin the personal computer 204.

[0266] The copyright management function 223 permits or inhibits thetransfer or copying of the content stored in the content database 224,in accordance with the usage conditions. When the content aretransferred or copied, the copyright management function 223 causes thecontent database 224 to update the usage conditions of the content.

[0267] The content database 224 records the content, content ID, contentinformation and content key, in the form of a single file of directorystructure.

[0268] The communication function 225 receives the content or thecontent information that has been transmitted from the PDA 203 or thepersonal computer 204 through the network 202. The communicationfunction 225 transmits the content or the content information to the PDA203 or the personal computer 204 through the network 202.

[0269]FIG. 21 is a diagram describing the function of the personalcomputer 204. The personal computer 204 has an authentication function241, a content display function 242, a content reproduction function243, a content management function 244, a copyright management function245, a content database 246, and a communication function 247.

[0270] The authentication function 241 incorporates a user database 251.The user database 251 records the authentication data (i.e., user ID orpassword, for example) of the user of the personal computer 204. Theauthentication function 241 authenticates the user of the personalcomputer 204, based on the data about the user operation and the userauthentication data. The user authentication data is recorded in theuser database 251.

[0271] The authentication function 241 stores the authentication key andthe like, which are necessary for the authentication process. Itauthenticates the server 201 via the network 202, by thechallenge-and-response method, on the basis of the data thecommunication function 247 has received and transmitted.

[0272] The content display function 242 has a display function 252 andan operation instructing function 253. The display function 252 displaysthe additional data associated with the content and contained in thecontent information that is recorded in the content database 246.

[0273] When the operation instructing function 253 receives the datarepresenting a user's operation, such as clicking on the screen, itinstructs the content reproduction function 243 to reproduce the contentand the display function 252 to update the display.

[0274] When the operation instructing function 253 receives the datarepresenting a user's operation, such as drag and drop, it instructs thecontent management function 224 to transfer or copy the content, or totransmits a request for the transfer or copying of the content to thecommunication function 247.

[0275] The content reproduction function 243 decodes the contentrecorded in the content database 246 in accordance with the instructionsupplied from the operation instructing function 247, thus reproducingthe content. When the content reproduction function 243 reproduces thecontent, it causes the copyright management function 245 to update theusage conditions that are recorded in the content database 246.

[0276] The communication function 247 may receive the contentinformation from the server 201. In accordance with the contentinformation the function 247 has received, the content managementfunction 244 causes the content database 246 to update the content data.

[0277] When the content are reproduced, transferred or copied, thecontent management function 244 causes the content database 246 toupdate the content information and to transmit the content informationupdated to the communication function 247 through the network 202.

[0278] The content management function 244 may receive from theoperation instructing function 253 an instruction for the transfer orcopying of the content within the content database 246. (Theinstructions include an instruction for the transfer or copying of thecontent from the personal computer 204 to the hard disc drive 205, andan instruction for the transfer or copying of the content from the harddisc drive 205 to the personal computer 204.) If this is the case, thecontent management function 244 asks the copyright management function245 whether the transfer or copying of the content is permitted or not.If it is determined that the transfer or copying is permitted, from theusage conditions that are recorded in the content database 246, thecontent management function 244 causes the content database 246 totransfer or copy the content. The content management function 244instructs the copyright management function 245 to update the usageconditions of both the data source and the data destination.

[0279] The content management function 244 may receive from the server201 an instruction for the transfer or copying of the content within thecontent database 246. (These instructions include an instruction for thetransfer or copying of the content from the personal computer 204 to thehard disc drive 205, and an instruction for the transfer or copying ofthe content from the hard disc drive 205 to the personal computer 204.)In this case, the content management function 244 asks the copyrightmanagement function 245 whether the transfer or copying of the contentis permitted or not. If it is determined that the transfer or copying ispermitted, from the usage conditions that are recorded in the contentdatabase 246, the content management function 244 causes the contentdatabase 246 to transfer or copy the content. The content managementfunction 244 instructs the copyright management function 245 to updatethe usage conditions of both the data source and the data destination.

[0280] If the copyright management function 245 determines that thetransfer or copying of the content is not permitted, the contentmanagement function 244 will not transfer or copy the content.

[0281] The content management function 244 may receive from theoperation instructing function 253 an instruction for the transfer ofcopying of the content from the content database 246 to the server 201.If so, the function 244 asks the copyright management function 245 ifthe transfer or copying of the content has been permitted. If thefunction 244 determines that the transfer or copying of the content hasbeen permitted, it causes the communication function 247 to transmit thecontent to the server 201, along with the content ID and the file nameof the destination (to which the content will be copied). The file nameincludes a path name.

[0282] If the copyright management function 245 determines that thetransfer or copying of the content is not permitted, the contentmanagement function 244 will cause the communication function 247 not totransmit the content.

[0283] The content management function 244 may receive from theoperation instructing function 253 an instruction for the transfer orcopying of the content from the content database 246 to the PDA 203. Ifthis is the case, the function 244 asks the copyright managementfunction 245 if the transfer or copying of the content has beenpermitted. If the function 245 determines that the transfer or copyingof the content has been permitted, the content management function 244causes the communication function 247 to transmit the content to the PDA203.

[0284] The content is transmitted, along with the content ID and thefile name of the destination (to which the content will be copied). Itshould be noted that the file name includes a path name.

[0285] If the copyright management function 245 determines that thetransfer or copying of the content has not been permitted, the contentmanagement function 244 will not transmit the content to the contentmanagement function 244.

[0286] When the communication function 247 receives a request for thetransfer or copying of the content from the content database 246 to theserver 201, the content management function 244 asks the copyrightmanagement function 245 whether the transfer or copying of the contentis permitted or not. If the function 245 determines that the transfer orcopying of the content is permitted, the content management function 244causes the communication function 247 to transmit the content, alongwith the content ID and the file name of the destination (to which thecontent will be copied). The file name includes a path name.

[0287] If the function 245 determines that the transfer or copying ofthe content is not permitted, the content management function 244 causesthe communication function 247 not to transmit the content.

[0288] When the communication function 247 may receive from the server201 an instructions for the transfer or copying of the content from thecontent database 246 to the PDA 203. In this case, the contentmanagement function 244 asks the copyright management function 245whether the transfer or copying of the content is permitted or not. Ifthe copyright management function 245 determines that the transfer orcopying is permitted, the content management function 244 causes thecommunication database 247 to transmit the content to the PDA 203. Thecontent is transmitted, along with the content ID and the file name ofthe destination (to which the content will be copied). Note that thefile name includes a path name.

[0289] If the copyright management function 245 determines that thetransfer or copying is not permitted, the content management function244 causes the communication function 247 not to transmit the content.

[0290] Assume that the communication function 247 receives aninstruction for the transfer or copying of the content to the personalcomputer 204. Then, the content management function 244 causes thecontent database 246 to record the content received and instructs thecopyright management function 245 to update the usage conditions of thecontent received.

[0291] In accordance with the usage conditions of the content, thecopyright management function 245 allows or inhibits the contentrecorded in the content database 246, from being reproduced, transferredor copied. When the content are reproduced, transferred or copied, thefunction 245 causes the content database 246 to update the usageconditions of the content.

[0292] The content database 246 records the content, content ID, contentinformation, content usage conditions and content key, in the form of asingle file of directory structure.

[0293] The communication function 247 receives the content or thecontent information that has been transmitted from the server 201 or thePDA 203 through the network 202. The communication function 247transmits the content or the content information to the server 201 orthe PDA 203 through the network 202.

[0294] The PDA 203 has the same structure as the personal computer 204.Therefore, the structure of the PDA 203 is not described herein.

[0295]FIG. 22 is a diagram illustrating an example of the contentinformation that is recorded in the content database 224 of the server201, the content database 246 of the personal computer 204, or thecontent database of the PDA 203.

[0296] The content information comprises various data items. The dataitems include a device connected, a content ID, a device ID, a devicename, connection data, additional data, usage conditions, a file name,and display data. The device connected is the ID of a device whichrecords the content and which is connected to the server 201.

[0297] The connection data represents whether or not the sever 201 isconnected to the device that records the content. If the connection datais “TRUE,” the device is connected to the server 201. If the connectiondata is “FALSE,” the device is not connected to the server 201.

[0298] The device name is the name of the device which records thecontent and which corresponds to the device ID. The user may give anydesirable name to the device.

[0299] The additional data includes the name of content, the recordingdate of content, and the type of content.

[0300] The usage condition includes an authorized user, a copy count, atransfer count, and a reproduction count. The authorized user may be theuser ID that identifies the user. The user ID may be used as a usagecondition, along the name of the user.

[0301] The file name contains a so-called “path.”

[0302] The display data includes an artist name, a release date, and analbum name.

[0303] In the content information of FIG. 22, the content identifiedwith the content ID “0001” is recorded in the server 201 identified bythe device ID “0001.” The name of content is “music A.” The recordingdate of content identified with the content ID “0001” is 2000/1/15. Thecontent identified with the content ID “0001” are encoded by MP3 (MPEGaudio layer-3) system. Therefore, the device ID associated with thecontent ID “0001” is “0001,” the name of content, associated with thecontent ID “0001,” is “music A,” the recording date of content,associated with the content ID “0001,” is 2000/1/15, and the type ofcontent, associated with the content ID “0001,” is “mp3.”

[0304] In the content information of FIG. 22, too, the server 201identified with the device ID “0001” has the device name “server.”

[0305] Since the content having the content ID “0001” is recorded in theserver 201, the connection data associated with the content ID “0001” is“TRUE.” Since the content having the content ID “0001” is recorded inthe server 201, the device connected, which is associated with thecontent ID “0001,” is “null.”

[0306] The user authorized to use the content identified with thecontent ID “0001” is “Paul.” Therefore, Paul can use the contentidentified with the content ID “0001.” Since the copy count for thecontent identified with the content ID “0001,” i.e., the number of timesthe content ID “0001” can be copied, is “0,” the content cannot becopied at all.

[0307] The transfer count for the content identified with the content ID“0001,” i.e., the number of times the content can be transferred, is“3.” Therefore, the content ID “0001” can be transferred three times.Since the reproduction count for the content identified with the contentID “0001,” i.e., the number of times the content can be copied, is “10,”the content ID “0001” can be reproduced ten times.

[0308] The content identified with the content ID “0001” is recorded inthe file having the name “audio1” that is recorded in the directory thepath of which is ¥ROOT ¥AUDIO. Hence, the file name associated with thecontent ID “0001” is “¥ROOT ¥AUDIO ¥audio1.”

[0309] The display data associated with the content ID “0001” includesan artist name “aaa” and a release date “bbb.”

[0310] In the content information of FIG. 22, the content identifiedwith the content ID “0002” and recorded in the personal computer 204that is identified with the device ID “0002” has the content name “musicB.” The recording date of the content identified with content ID “0002”is 2000/2/5. Further, the content identified with content ID “0002” isencoded by MP3 system. Therefore, the device ID associated with thecontent ID “0002” is “0002,” the name of content, associated with thecontent ID “0002,” is “music B,” the recording date of content,associated with the content ID “0002,” is 2000/2/5, and the type ofcontent, associated with the content ID “0002,” is “mp3.”

[0311] In the content information of FIG. 22, the personal computer 204the device ID of which is “0002” has the device name “PC.”

[0312] The personal computer 204 that records the content having thecontent ID of “0002” is connected to the server 201. Hence, theconnection data associated with the content ID “0002” is “TRUE.” Sincethe personal computer 204 that records the content having the content IDof “0002” is connected to the server 201, the connected deviceassociated with the content ID “0002” has the device ID of “0001,” whichis the server 201.

[0313] Since the user authorized to use the content the content ID ofwhich is “0002” is “Paul,” Paul can use the content identified by thecontent ID “0002.” Since the number of times the content identified bythe content ID “0002” can be copied is “0,” these content cannot becopied at all.

[0314] Since the number of times the content identified by the contentID “0002” can be transferred is “3,” these content can be transferredthree times. Since the number of times the content identified by thecontent ID “0002” can be reproduced is “10,” the content can bereproduced ten times.

[0315] The content identified with the content ID “0002” is recorded inthe file having the name “audio2” that is recorded in the directory thepath of which is ¥ROOT ¥AUDIO. Hence, the file name associated with thecontent ID “0002” is “¥ROOT ¥AUDIO ¥audio2.”

[0316] The display data associated with the content ID “0002” includesan artist name “ccc” and a release date “ddd.”

[0317] In the content information of FIG. 22, the content identifiedwith the content ID “0003” and recorded in the personal computer 204that is identified with the device ID “0002” has the content name “imageC.” The recording date of the content identified with content ID “0003”is 2000/8/30. Further, the content identified with content ID “0003” isencoded by JPEG (Joint Photographic Experts Group) system. Therefore,the device ID associated with the content ID “0003” is “0002,” the nameof content, associated with the content ID “0003,” is “image C,” therecording date of content, associated with the content ID “0003,” is2000/8/30, and the type of content, associated with the content ID“0003,” is “jpeg.”

[0318] The personal computer 204 that records the content having thecontent ID of “0003” is connected to the server 201. Hence, theconnection data associated with the content ID “0003” is “TRUE.” Sincethe personal computer 204 that records the content having the content IDof “0003” is connected to the server 201, the connected deviceassociated with the content ID “0003” has the device ID of “0001.” Thus,this device is the server 201.

[0319] Since the user authorized to use the content the content ID ofwhich is “0003” is “Paul,” Paul can use the content identified by thecontent ID “0003.” Since the number of times the content identified bythe content ID “0003” can be copied is “1,” these content can be copiedonce.

[0320] Since the number of times the content identified by the contentID “0003” can be transferred is “3,” these content can be transferredthree times. Since the number of times the content identified by thecontent ID “0003” can be reproduced is “10,” the content can bereproduced ten times.

[0321] The content identified with the content ID “0003” is recorded inthe file having the name “image1” that is recorded in the directory thepath of which is ¥ROOT ¥IMAGE. Hence, the file name associated with thecontent ID “0003” is “¥ROOT ¥IMAGE ¥image1.”

[0322] The display data associated with the content ID “0003” includesan artist name “eee” and a release date “fff.”

[0323] In the content information of FIG. 22, the content identifiedwith the content ID “0004” and recorded in the hard disc drive 205 thatis identified with the device ID “0003” has the content name “music D.”The recording date of the content identified with content ID “0004” is2000/9/15. Further, the content identified with content ID “0004” isencoded by ATRAC (Adaptive Transform Acoustic Coding)-3(trade name),system. Therefore, the device ID associated with the content ID “0004”is “0003,” the name of content, associated with the content ID “0004,”is “music D,” the recording date of content, associated with the contentID “0004,” is 2000/9/15, and the type of content, associated with thecontent ID “0004,” is “at3.”

[0324] In the content information of FIG. 22, the hard disc drive 205the device ID of which is “0003” has a device name of “hard disc drive.”

[0325] The hard disc drive 205 that records the content having thecontent ID of “0004” is connected to the server 201 by the personalcomputer 204. Hence, the connection data associated with the content ID“0004” is “TRUE.” Since the hard disc drive 205 that records the contenthaving the content ID of “0004” is connected to the server 201 by thepersonal computer 204, the connected device associated with the contentID “0004” has the device ID of “0002,” which is the personal computer204.

[0326] Since the user authorized to use the content the content ID ofwhich is “0004” is “Kevin,” Kevin can use the content identified by thecontent ID “0004.” Since the number of times the content identified bythe content ID “0004” can be copied is “2,” these content cant be copiedtwice.

[0327] Since the number of times the content identified by the contentID “0004” can be transferred is “2,” these content can be transferredtwice. Since the number of times the content identified by the contentID “0004” can be reproduced is “20,” the content can be reproduced 20times.

[0328] The content identified with the content ID “0004” is recorded inthe file having the name “audio3” that is recorded in the directory thepath of which is ¥ROOT ¥AUDIO. Hence, the file name associated with thecontent ID “0004” is “¥ROOT ¥AUDIO ¥audio3.”

[0329] The display data associated with the content ID “0004” includesan artist name “ggg” and a release date “hhh.”

[0330] In the content information of FIG. 22, the content identifiedwith the content ID “0005” and recorded in the PDA 203 that isidentified with the device ID “0004” has the content name “image E.” Therecording date of the content identified with content ID “0005” is2000/6/1. Further, the content identified with content ID “0005” isencoded by GIF (Graphic Interchange Format) system. Therefore, thedevice ID associated with the content ID “0005” is “0004,” the name ofcontent, associated with the content ID “0005,” is “image E,” therecording date of content, associated with the content ID “0005,” is2000/6/1, and the type of content, associated with the content ID“0005,” is “gif.”

[0331] In the content information of FIG. 22, the PDA 203 whose deviceID is “0004” has a device name of “PDA.”

[0332] The PDA 203 that records the content having the content ID of“0005” is not connected to the server 201. Hence, the connection dataassociated with the content ID “0005” is “FALSE.” Since the PDA 203 thatrecords the content having the content ID of “0005” was connected to theserver 201, the connected device associated with the content ID “0005”has the device ID of “0001,” which is the server 201.

[0333] Since the user authorized to use the content the content ID ofwhich is “0005” is “Jamie,” Jamie can use the content identified by thecontent ID “0005.” Since the number of times the content identified bythe content ID “0005” can be copied is “5,” these content can be copiedfive times.

[0334] Since the number of times the content identified by the contentID “0005” can be transferred is “4,” these content can be transferredfour times. Since the number of times the content identified by thecontent ID “0005” can be reproduced is “50,” the content can bereproduced 50 times.

[0335] The content identified with the content ID “0005” is recorded inthe file having the name “image2” that is recorded in the directory thepath of which is ¥ROOT ¥IMAGE . Hence, the file name associated with thecontent ID “0005” is “¥ROOT ¥IMAGE ¥image2.”

[0336] The display data associated with the content ID “0005” includesan artist name “iii” and a release date “jjj.”

[0337]FIG. 23 is an image the personal computer 204 displays uponreceiving the content information shown in FIG. 22.

[0338] As FIG. 23 shows, the server 201, which is the root, records thecontent “music A.” The personal computer 204 and the PDA 203 areconnected to the server 201. Therefore, the icons of the content “musicA,” personal computer 204 and PDA 203 are arranged on the right of theicon of the server 201.

[0339] The personal computer 204 records the content “music B” and thecontent “image C.” The hard disc drive 205 is connected to the personalcomputer 204. Therefore, the icons of the contents “music B” and “imageC” and the icon of the hard disc drive 205 are arranged on the right ofthe icon of the personal computer 204.

[0340] The hard disc drive 205 records the content “music D.” Thus, theicon of the content “music D” is arranged on the right of the icon ofthe hard disc drive 205.

[0341] The PDA 203 records the content “image E.” Therefore, the icon ofthe content “image E” is arranged on the right of the icon of the PDA203.

[0342] The PDA 203 is not connected to the server 201. Thus, the icon ofthe PDA 203 and the icon of the content “image E” are displayed in acolor different from the icon of the content “music A.” This indicatesthat the PDA 203 recorded the content “image E” when it was connected tothe server 201.

[0343] The icon of the content “music B,” for example, may be clicked asshown in FIG. 24. In this case, the personal computer 204 displays theartist name “ccc” and the release date “ddd,” both associated with thecontent “music B.”

[0344] The personal computer 204 may display usage conditions of acontent when the icon of this content is clicked.

[0345] The user may drag the icon of the content “image C” and then dropit at the icon of the hard disc drive 205. If this is the case, thepersonal computer 204 will transfer the content “image C” to the harddisc drive 205.

[0346] When the personal computer 204 transfers the content “image C” tothe hard disc drive 205, it updates the content information. The contentinformation updated is supplied to the server 201.

[0347] The server 201 updates the content information it records, basedon the content information received from the personal computer 204. Thecontent information thus updated is supplied to the personal computer204.

[0348]FIG. 25 is the content information that the personal computer 204displays when the content “image C” is transferred to the hard discdrive 205.

[0349] Since the content “image C” identified with the content ID “0003”has been transferred to the hard disc drive 205, the device IDassociated with the content ID “0003” is “0003,” identifying the harddisc drive 205, and the device name associated with the content ID“0003” is “hard disc drive.”

[0350] The device connected, which is associated with the content ID“0003,” is “0002,” which designates the personal computer 204.

[0351] The personal computer 204 receives the content informationupdated when the content “image C” is transferred. At this time thepersonal computer 204 arranges the icons of the content “music D” andcontent “image C” at the right of the icon of the hard disc drive 205,as is illustrated FIG. 26.

[0352] How the content display system that has the structure of FIG. 19displays the content information will be described, with reference tothe flowchart of FIG. 27.

[0353] In Step S201, the server 201 determines via the network 202whether a device such as the PDA 203 or the personal computer 204 hasbeen connected to it. If the server 201 determines that a device hasbeen connected to it, the operation goes to Step S202. In Step S202, adevice-connecting process is performed. The device-connecting processwill be described later in detail.

[0354] If the server 201 determines that a device has not been connectedto it, the operation jumps to Step S203, skipping Step S202. This isbecause the device-connecting process need not be carried out.

[0355] In Step S203, the server 201, the PDA 203 or the personalcomputer 204 determines whether the transfer of a content has beenrequested. If it is determined that the transfer of a content has beenrequested, the operation goes to Step S204. In Step S204, the server201, the PDA 203 or the personal computer 204 transfers the content.When the server 201 transfers the content, it updates the contentinformation. How the server 201 updates the content information will beexplained later in detail.

[0356] If it is determined in Step S203 that the transfer of a contenthas not been requested, the operation jumps to Step S205, skipping StepS204. This is because the content need not be transferred at all.

[0357] In Step S205, the server 201 determines whether the contentinformation has been updated. If the content information is determinedto have been updated, the operation goes to step S206. In Step S206, theserver 201 distributes the content information to the PDA 203 and thepersonal computer 204. The PDA 203 and the personal computer 204 displaythe image corresponding to the content information. How the server 201distributes the content information will be described later in detail.

[0358] If it is determined in Step S205 that the content information hasnot been updated, the operation jumps to Step S207, skipping Step S206.This is because the content information need not be distributed at all.

[0359] In Step S207, the server 201 determines whether a device such asthe PDA 203 or the personal computer 204 has been disconnected from it.If the device is determined to have been disconnected, the operationadvances to Step S208. In Step S208, a device-disconnecting process isperformed. Then, the operation returns to Step S201, and Steps S201 toS208 will be repeated.

[0360] If it is determined in Step S207 that the device has beendisconnected, the operation returns to Step S201. This is because thedevice-disconnecting process need not be carried out.

[0361] In the content display system shown in FIG. 19, the content istransferred whenever the transfer of the content is requested. Thecontent information is distributed whenever the content information isupdated. When the content is transferred to them, the PDA 203 and thepersonal computer 204 display the information about the content, basedon the content information that has been updated.

[0362] In the content display system, the content may be not onlytransferred, but also reproduced, copied and deleted. Whenever the stateof the content changes, the content information may be updated, and thecontent information thus updated may be distributed.

[0363] The device-connecting process is effected in Step S202 when thepersonal computer 204 is connected to the server 201. How the process isperformed will be described with reference to the flowchart of FIG. 28.

[0364] In Step S11001, the authentication function 221 provided in theserver 201 authenticates the personal computer 204 by thechallenge-and-response method or the like. If the personal computer 204is not authenticated as one that can be connected, the device-connectingprocess is terminated and will not be performed on the personal computer204.

[0365] In Step S21001, the authentication function 241 provided in thepersonal computer 204 authenticates the server 201. If the server 201 isnot authenticated as one that can be connected, the device-connectingprocess is terminated. The content information is not updated.

[0366] In Step S 11001 the personal computer 204 may be authenticated asone that can be connected, and in Step S21001 the server 201 may beauthenticated as one that can be connected. If this is the case, theoperation goes to Step S11002. In Step S11002, the authenticate function221 of the server 201 authenticate the user of the personal computer204, based on the information supplied from the personal computer 204.If the function 221 does not authenticate the user of the personalcomputer 204 as an authorized user, the process is terminated, and thecontent information will not be updated.

[0367] If the user of the personal computer 204 may be found anauthorized one in Step S11002, the process goes to Step S11003. In StepS11003, the content management function 222 of the server 201 readscontent information from the content database 224. The communicationfunction 225 transmits the content information, thus read, to thepersonal computer 204 through the network 202.

[0368] In Step S21002, the communication function 247 of the personalcomputer 204 receives the content information transmitted from theserver 201. In Step S21003, the content management function 244 of thepersonal computer 204 updates the content information stored in thecontent database 246, based on the content information the computer 204has received from the server 201.

[0369] In Step S21004, the content management function 244 of thepersonal computer 204 reads the content information from the contentdatabase 246. The communication function 247 transmits the contentinformation, thus read, to the server 201 through the network 202.

[0370] In Step S11004, the communication function 225 of the server 201receives the content information transmitted from the personal computer204. In Step S11005, the content management function 222 discards thecontent information about the computer 204 from the content database224.

[0371] In Step S1106, the content management 222 updates the contentinformation stored in the content database 224, based on the contentinformation received from the personal computer 204. The process is thenterminated.

[0372] Thus, the content information recorded in the server 201 isupdated when any device is connected to the server 201, and the contentinformation recorded in the device is also updated when it is connectedto the server 201.

[0373] The user of the PDA 203 may drag the icon of the content,displayed on the PDA 203 and drop it at the icon of the server 201,requesting that the content be transferred from the PDA 203 to theserver 201. In this case, the personal computer 204 transfers thecontent to the PDA 203 in Step S204, as will be described with referenceto the flowchart of FIG. 29.

[0374] In Step S12001, the communication function 225 of the server 201transmits a request for the transfer of the content to the personalcomputer 204 via the network 202.

[0375] In Step S22001, the communication function 247 of the personalcomputer 204 receives the request for the transfer of the content. InStep S22002, the copyright management function 245 of the personalcomputer 204 checks the usage conditions for the content, which arerecorded in the content database 246 of the personal computer 204. Ifnone of the usage conditions allow the transfer of the content, thecontent is not transferred and the process is terminated. If any one ofthe usage conditions allows the transfer of the content, the operationgoes to Step S22003. In Step S22003, the content management function 244of the personal computer 204 reads the content from the content database246 of the personal computer 204. The communication function 247transmits the content to the PAD 2.

[0376] In Step S32001, the communication function of the PDA 203receives the content. In Step S32002, the copyright management functionof the PDA 203 updates the usage conditions in accordance with thecontent the PDA 203 has received.

[0377] In Step S22004, the copyright management function 245 of thepersonal computer 204 updates the usage conditions stored in the contentdatabase 246 and associated with the content transmitted to the PDA 203.In Step S22005, the content management function 244 of the personalcomputer 204 updates the content information about the contenttransmitted to the PDA 203. In Step S22006, the content managementfunction 244 causes the communication function 247 to transmit thecontent information to the server 201 through the network 202.

[0378] In Step S12002, the communication function 225 of the sever 201receives the content information transmitted from the personal computer204. In Step S12003, the content management function 222 discards thecontent information about the personal computer 204 from the contentdatabase 224.

[0379] In Step S32003, the content management function of the PDA 203updates the content information in accordance with the content that thePDA 203 has received.

[0380] In Step S32004, the communication function of the PDA 203transmits the content information to the server 201 through the network202.

[0381] In Step S12004, the communication function 225 of the server 201receives the content information the content information transmittedfrom the PDA 203. In Step S12005, the content management function 222discards the content information about the PDA 203 from the contentdatabase 224.

[0382] In Step S12006, the content management function 222 of the server201 updates the content information stored in the content database 224,based on the content information received from the personal computer 204and the content information received from the PDA 203. The process isthen terminated

[0383] Thus, the server 201, the personal computer 204 and the PDA 203can transfer the content and update the content information associatedwith the content transferred.

[0384] The content can be transferred from the PDA 203 to the personalcomputer 204 in the same manner as has been described. Therefore, howthe content is so transferred will not be described.

[0385] The user of the personal computer 204 may drag the icon of thecontent, displayed on the display and drop it at the icon of the server201, requesting that the content be transferred from the server 201 tothe personal computer 204. In this case, the content is transferred fromthe server 201 to the personal computer 204 in Step S204, as will bedescribed with reference to the flowchart of FIG. 30.

[0386] In Step S13001, the copyright management function 223 of theserver 201 checks the usage conditions for the content, which arerecorded in the content database 224 of the server 201. If none of theusage conditions allow the transfer of the content, the content is nottransferred and the process is terminated. If any one of the usageconditions allows the transfer of the content, the operation goes toStep S13002. In Step S13002, the content management function 222 of theserver 201 reads the content from the content database 224 of the sever201. The communication function 225 transmits the content to thepersonal computer 204.

[0387] In Step S13003, the copyright management function 223 of theserver 201 updates the usage conditions associated with the content andstored in the content database 224 of the sever 201.

[0388] In Step S23001, the communication function 247 of the personalcomputer 204 receives the content. In Step S23002, the copyrightmanagement function 245 of the computer 204 updates the usage conditionsassociated with the content, in the content database 246 of the server201.

[0389] In Step S23003, the content management function 244 of thepersonal computer 204 updates the content information stored in thecontent database 246, in accordance with the content received. In StepS23004, the communication function 247 of the personal computer 204transmits the content information to the server 201 through the network202.

[0390] In Step S13004, the communication function 225 of the server 201receives the content information transmitted from the personal computer204. In Step S13005, the content management function 222 discards thecontent information about the personal computer 204 from the contentdatabase 224.

[0391] In Step S13006, the content management function 222 of the sever201 updates the content information stored in the content database 224,based on the content information received from the personal computer204. The process is then terminated.

[0392] Thus, the server 201 and the personal computer 204 can transferthe content and update the content information associated with thecontent transferred.

[0393] The content can be transferred from the server 201 to the PDA203, from the personal computer 204 to the server 201, and from the PDA203 to the server 201, in the same way. How the content is sotransferred will not be described.

[0394] How the content information is distributed in Step S206 (FIG. 27)when the content information is updated will be described, withreference to the flowchart of FIG. 31.

[0395] In Step S14001, the communication function 225 of the server 201transmits the content information to the PDA 203 through the network202.

[0396] In Step S34001, the communication function of the PDA 203receives the content information transmitted from the sever 201. In StepS34002, the content management function of the PDA 203 updates thecontent information stored in the PDA 203, in accordance with thecontent information received. In Step S34003, the content displayfunction of the PDA 203 displays the content information updated.

[0397] In Step S14002, the communication function 225 of the server 201transmits the content information to the personal computer 204 throughthe network 202.

[0398] In Step S24001, the communication function 247 of the personalcomputer 204 receives the content information transmitted from theserver 201. In Step S24002, the content management function 244 of thepersonal computer 204 updates the content information stored in thecomputer 204, in accordance with the content information received. InStep S24003, the content display function 242 of the personal computer204 displays the content information updated. The process is thenterminated.

[0399] Thus, the content information is distributed to any deviceconnected to the server 201, when the content information is updated.

[0400] Assume that an N number of devices are connected to the server201. In this case, the server 201 distributes the content informationupdated, to each of these devices.

[0401] How the device-disconnection process is performed in Step S208(FIG. 27) will be explained, with reference to the flowchart of FIG. 32.

[0402] In Step S15001, the content management function 222 of the server201 updates the content information in the content database 224, settingthe connection flag at “false.” Then, the process is terminated. Notethat the flag is concerned with the content of the device disconnectedfrom the server 201.

[0403] When the personal computer 204, for example, is disconnected fromthe server 201, the content management function 222 updates the contentinformation in the content database 224, setting the connection flag at“false,” which is concerned with the content stored in the personalcomputer 204.

[0404] Thus, the server 201 updates the connection flag contained in thecontent information and concerned with the content stored in the devicedisconnected from the server 201, when the process of displaying thecontent is terminated.

[0405] As described above, the server 201 is connected by the network202 to the PDA 203 and the personal computer 204. Nonetheless, theserver 201 can be connected to not only the PDA 203 and the personalcomputer 204, but also other types of devices. It can be connected to,for example, a mobile telephone, a PHS terminal, a digital still camera,a digital video camera, a car navigation device, a television receiver,a radio receiver, or a portable device. The server 201 operates in thesame way as described above, to whichever device it is connected.

[0406] As indicated above, the server 201 is connected to the PDA 203and the personal computer 204 by the network 202. Instead, the server201 may be connected to the PDA 203 and the computer 204 by a wire orwireless media, such as the public telephone line, the mobile telephoneline, the PHS, the Internet, the Bluetooth network, or the digitalsatellite broadcasting network.

[0407] Further, the content that the server 201, the PDA 203 or thepersonal computer 204 records is not limited to music or images. Rather,it may be voice, characters, programs or data for executing a program.

[0408] As described above, the content is encrypted by the DES system.Nonetheless, it may be encrypted into a block code or stream code ofanother common-key system, or into a code of a public-key system.

[0409] The sequence of operations, described above, can be performed notonly by hardware, but also by software. To perform the sequence by usingsoftware, the programs constituting the software are installed from arecording medium into a dedicated computer or a general-purposecomputer.

[0410] The recording medium is distributed to users to provide them withthe programs. The recording medium may be a package media such as amagnetic disc 51 (including a floppy disc), an optical disc 52 (CD-ROM(Compact Disc-Read Only Memory)), a DVD (Digital Versatile Disc), amagneto-optical disc 53 (MD (Mini-Disc), or a semiconductor memory 54,as is illustrated in FIG. 2. Alternatively, the recording medium may bethe ROM 22 or the hard disc provided in the recording section 29, eitherincorporated in the personal computer 1.

[0411] If necessary, the programs for executing the sequence ofoperations may be installed into the computer through an interface suchas a router or a modem. Alternatively, they may be installed into thecomputer through a wire or wireless medium such as a local area network,the Internet or the digital satellite-broadcasting network.

[0412] The steps describing any program stored in the recording mediumare performed in the time sequence specified above in the presentspecification. Instead, some of them may be carried out in parallel orindependently of one another.

[0413] The word “system” used in this specification means an apparatusthat comprises a plurality of devices.

[0414] Industrial Applicability

[0415] According to the information providing apparatus, informationproviding method and recording medium of the present invention, aninformation processing device is authenticated via a transmission path,and the usage conditions of a content and information about the contentare held. The reception of the usage condition and the information aboutthe content is controlled. The usage condition and the information,which are held, are updated based on the usage conditions and theinformation received. Hence, any desired content can be retrievedquickly, and a copyrighted content can be easily transferred and copiedin accordance with the usage conditions.

[0416] According to the information providing apparatus, informationproviding method and recording medium of the present invention, theusage conditions of a content and information about the content areheld. When the content is operated the usage condition and theinformation held are updated. When the information providing apparatusis authenticated via the transmission path and the content is operated,the transmission of the usage condition and information is controlled.The reception of the usage conditions and information about thecontents, transmitted from the information providing apparatus, iscontrolled. The usage conditions and the information, which are held,are updated, and the display of the information is controlled. Hence,any desired content can be retrieved quickly, and a copyrighted contentcan be easily transferred and copied in accordance with the usageconditions.

1. An information providing apparatus for providing information about acontent via a transmission path to a first information processing devicewhich stores the content on the basis of usage conditions restrictingthe operation of the content, said apparatus comprising: deviceauthentication means for authenticating the first information processingdevice via the transmission path; holding means for holding the usageconditions and the information about the content; first receptioncontrol means for controlling the reception of the usage conditions andthe information about the content, which have been transmitted from thefirst information processing device; and updating means for updating theusage conditions and the information, which are held, on the basis ofthe usage conditions and information which have been received.
 2. Theinformation providing apparatus according to claim 1, further comprisingtransmission control means for controlling the transmission to a secondinformation processing device when the information is updated.
 3. Theinformation providing apparatus according to claim 1, further comprisingdisplay control means for controlling the display of the informationabout the content.
 4. The information providing apparatus according toclaim 1, further comprising: second reception control means forcontrolling the reception of a request for the operation of the content,transmitted from the first information processing device; andtransmission control means for controlling the transmission of therequest for the operation of the content, to the second informationprocessing device.
 5. The information providing apparatus according toclaim 1, further comprising: means for determining whether the operationof the content should be permitted; and operating means for operatingthe content when it is determined that the operation of the contentshould be permitted.
 6. The information providing apparatus according toclaim 1, further comprising user authentication means for authenticatinga user of the information providing apparatus.
 7. The informationproviding apparatus according to claim 1, further comprising userauthentication means for authenticating a user of the first informationprocessing device.
 8. The information providing apparatus according toclaim 1, wherein the holding means further holds a flag indicatingwhether the first information processing device is connected by thetransmission path, and the updating means updates the flag.
 9. Aninformation providing method of providing information about a contentvia a transmission path to an information processing device which storesthe content on the basis of usage conditions restricting the operationof the content, said method comprising the steps of: authenticating thefirst information processing device via the transmission path; holdingthe usage conditions and the information about the content; controllingthe reception of the usage conditions and the information about thecontent, which have been transmitted from the information processingdevice; and updating the usage conditions and the information, which areheld, on the basis of the usage conditions and information which havebeen received.
 10. A recording medium that records a program forproviding information about a content via a transmission path to aninformation processing device which stores the content on the basis ofusage conditions restricting the operation of the content, said programdescribing the steps of: authenticating the information processingdevice via the transmission path; holding the usage conditions and theinformation about the content; controlling the reception of the usageconditions and the information about the content, which have beentransmitted from the information processing device; and updating theusage conditions and the information, which are held, on the basis ofthe usage conditions and information which have been received.
 11. Aninformation processing device connected to an information providingapparatus by a transmission path and designed to process a content onthe basis of usage conditions restricting the operation of the content,said device comprising: holding means for holding the usage conditionsof content and the information associated with the content; firstupdating means for updating the usage conditions and the information,held in the holding means, in accordance with the operation of thecontent if the content have been operated; apparatus authenticationmeans for authenticating an information providing apparatus though thetransmission path; first transmission control means for controlling thetransmission of the usage conditions and the information to theinformation providing apparatus when the content are operated; receptioncontrol means for controlling the reception of the usage conditions andthe information associated with the content, which have been transmittedfrom the information providing apparatus; second updating means forupdating the usage conditions and the information, both held, on thebasis of the usage conditions and the information which have beenreceived; and display control means for controlling the displaying ofthe information.
 12. The information processing device according toclaim 11, further comprising means for determining whether to permit anoperation of the content, in accordance with the usage conditions held;and operating means for operating the content if it has been determinedthat the operation of the content is permitted.
 13. The informationprocessing device according to claim 11, further comprising userauthentication means for authenticating a user of the informationprocessing device.
 14. The information processing device according toclaim 11, further comprising second transmission control means forcontrolling the transmission of a content operation request to theinformation providing apparatus.
 15. An information processing methodfor use in a information processing device connected to an informationproviding apparatus by a transmission path and designed to process acontent on the basis of usage conditions restricting the operation ofthe content, said method comprising: a holding step of holding the usageconditions of content and the information associated with the content; afirst updating step of updating the usage conditions and theinformation, held in the holding means, in accordance with the operationof the content if the content have been operated; an apparatusauthentication step of authenticating an information providing apparatusthough a transmission path; a transmission control step of controllingthe transmission of the usage conditions and the information to theinformation providing apparatus when the content is operated; areception control step for controlling the reception of the usageconditions and the information associated with the content, which havebeen transmitted from the information providing apparatus; a secondupdating step of updating the usage conditions and the information, bothheld, on the basis of the usage conditions and the information whichhave been received; and a display control step of controlling thedisplaying of the information.
 16. A recording medium recording aprogram for use in a information processing device connected to aninformation providing apparatus by a transmission path and designed toprocess a content on the basis of usage conditions restricting theoperation of the content, said program describing: a holding step ofholding the usage conditions of content and the information associatedwith the content; a first updating step of updating the usage conditionsand the information, held in the holding means, in accordance with theoperation of the content if the content have been operated; an apparatusauthentication step of authenticating an information providing apparatusthough a transmission path; a transmission control step of controllingthe transmission of the usage conditions and the information to theinformation providing apparatus when the content is operated; areception control step of controlling the reception of the usageconditions and the information associated with the content, which havebeen transmitted from the information providing apparatus; a secondupdating step of updating the usage conditions and the information, bothheld, on the basis of the usage conditions and the information whichhave been received; and a display control step of controlling thedisplaying of the information.